Racial and Ethnic Disparities in Kidney Replacement Therapies Among Adults With Kidney Failure: An Observational Study of Variation by Patient Age.

Rationale & Objective: Non-Hispanic Black and Hispanic patients present with kidney failure at younger ages than White patients. Younger patients are also more likely to receive transplants and home dialysis than in-center hemodialysis (ICHD), but it is unknown whether racial and ethnic disparities in treatment differ by age. We compared use of kidney replacement therapies between racial and ethnic groups among patients with incident kidney failure overall and by age.

Study Design: Retrospective cohort study.

Setting & Participants: 830,402 US adult (age >21 years) patients initiating kidney failure treatment during the period of 2011-2018.

Exposures: Patient race and ethnicity (non-Hispanic Black, non-Hispanic White, Hispanic, or other) and age group (22-44, 45-64, 65-74, or 75-99 years).

Outcome: Treatment modality (transplant, peritoneal dialysis [PD], home hemodialysis [HHD], or ICHD) as of day 90 of treatment.

Analytical Approach: Differences in treatment modalities were quantified for patient subgroups defined by race and ethnicity and by age. Log-binomial regression models were fit to estimate adjusted risk ratios.

Results: 81% of patients were treated with ICHD, 3.0% underwent transplants (85% preemptive, 57% living-donor), 10.5% were treated with PD, and 0.7% were treated with HHD. Absolute disparities in treatment were most pronounced among patients aged 22-44 years. Compared with non-Hispanic White patients, whose percentages of treatment with transplant, PD, and HHD were 10.9%, 19.0%, and 1.2%, respectively, non-Hispanic Black patients were less commonly treated with each modality (unadjusted percentages, 1.8%, 13.8%, and 0.6%, respectively), as were Hispanic patients (4.4%, 16.9%, and 0.5%, respectively; all differences P < 0.001). After adjustment, the largest relative disparities were observed for transplant among the 22-44-year age group; compared with non-Hispanic White patients, the adjusted risk ratios for non-Hispanic Black and Hispanic patients were 0.21 (95% CI, 0.19-0.23) and 0.47 (95% CI, 0.43, 0.51), respectively.

Limitations: Race and ethnicity data not self-reported.

Conclusions: Among adults with incident kidney failure, racial and ethnic disparities in transplant and home dialysis use are most pronounced among the youngest adult patient age group.